package tablecloth-native

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Functions for manipulating tuples of length two

Functions for manipulating pairs of values

type ('a, 'b) t = 'a * 'b

Create

val make : 'a -> 'b -> 'a * 'b

Create a two-tuple with the given values.

The values do not have to be of the same type.

Examples

Tuple2.make 3 "Clementine" = (3, "Clementine")
val fromArray : 'a array -> ('a * 'a) option

Create a tuple from the first two elements of an Array.

If the array is longer than two elements, the extra elements are ignored.

If the array is less than two elements, returns None

Examples

Tuple2.fromArray [|1; 2|] = Some (1, 2)
Tuple2.fromArray [|1|] = None
Tuple2.fromArray [|4; 5; 6|] = Some (4, 5)
val from_array : 'a array -> ('a * 'a) option
val fromList : 'a list -> ('a * 'a) option

Create a tuple from the first two elements of a List.

If the list is longer than two elements, the extra elements are ignored.

If the list is less than two elements, returns None

Examples

Tuple2.fromList [1; 2] = Some (1, 2)
Tuple2.fromList [1] = None
Tuple2.fromList [4; 5; 6] = Some (4, 5)
val from_list : 'a list -> ('a * 'a) option
val first : ('a * 'b) -> 'a

Extract the first value from a tuple.

Examples

Tuple2.first (3, 4) = 3
Tuple2.first ("john", "doe") = "john"
val second : ('a * 'b) -> 'b

Extract the second value from a tuple.

Examples

Tuple2.second (3, 4) = 4
Tuple2.second ("john", "doe") = "doe"

Transform

val mapFirst : ('a * 'b) -> f:('a -> 'x) -> 'x * 'b

Transform the first value in a tuple.

Examples

Tuple2.mapFirst ~f:String.reverse ("stressed", 16) = ("desserts", 16)
Tuple2.mapFirst ~f:String.length ("stressed", 16) = (8, 16)
val map_first : ('a * 'b) -> f:('a -> 'x) -> 'x * 'b
val mapSecond : ('a * 'b) -> f:('b -> 'c) -> 'a * 'c

Transform the second value in a tuple.

Examples

Tuple2.mapSecond ~f:Float.squareRoot ("stressed", 16.) = ("stressed", 4.)
Tuple2.mapSecond ~f:(~-) ("stressed", 16) = ("stressed", -16)
val map_second : ('a * 'b) -> f:('b -> 'c) -> 'a * 'c
val mapEach : ('a * 'b) -> f:('a -> 'x) -> g:('b -> 'y) -> 'x * 'y

Transform both values of a tuple, using f for the first value and g for the second.

Examples

Tuple2.mapEach ~f:String.reverse ~g:Float.squareRoot ("stressed", 16.) = ("desserts", 4.)
Tuple2.mapEach ~f:String.length ~g:(~-) ("stressed", 16) = (8, -16)
val map_each : ('a * 'b) -> f:('a -> 'x) -> g:('b -> 'y) -> 'x * 'y
val mapAll : ('a * 'a) -> f:('a -> 'b) -> 'b * 'b

Transform both of the values of a tuple using the same function.

mapAll can only be used on tuples which have the same type for each value.

Examples

Tuple2.mapAll ~f:(Int.add 1) (3, 4, 5) = (4, 5, 6)
Tuple2.mapAll ~f:String.length ("was", "stressed") = (3, 8)
val map_all : ('a * 'a) -> f:('a -> 'b) -> 'b * 'b
val swap : ('a * 'b) -> 'b * 'a

Switches the first and second values of a tuple.

Examples

Tuple2.swap (3, 4) = (4, 3)
Tuple2.swap ("stressed", 16) = (16, "stressed")

Convert

val toArray : ('a * 'a) -> 'a array

Turns a tuple into an Array of length two.

This function can only be used on tuples which have the same type for each value.

Examples

Tuple2.toArray (3, 4) = [|3; 4|]
Tuple2.toArray ("was", "stressed") = [|"was"; "stressed"|]
val to_array : ('a * 'a) -> 'a array
val toList : ('a * 'a) -> 'a list

Turns a tuple into a list of length two. This function can only be used on tuples which have the same type for each value.

Examples

Tuple2.toList (3, 4) = [3; 4]
Tuple2.toList ("was", "stressed") = ["was"; "stressed"]
val to_list : ('a * 'a) -> 'a list

Compare

val equal : ('a -> 'a -> bool) -> ('b -> 'b -> bool) -> ('a, 'b) t -> ('a, 'b) t -> bool

Test two Tuple2s for equality, using the provided functions to test the first and second components.

Examples

Tuple2.equal Int.equal String.equal (1, "Fox") (1, "Fox") = true
Tuple2.equal Int.equal String.equal (1, "Fox") (2, "Hen") = false
val compare : ('a -> 'a -> int) -> ('b -> 'b -> int) -> ('a, 'b) t -> ('a, 'b) t -> int

Compare two Tuple2s, using the provided functions to compare the first components then, if the first components are equal, the second components.

Examples

Tuple2.compare Int.compare String.compare (1, "Fox") (1, "Fox") = 0
Tuple2.compare Int.compare String.compare (1, "Fox") (1, "Eel") = 1
Tuple2.compare Int.compare String.compare (1, "Fox") (2, "Hen") = -1